[AMPS] Triode PSUs

[Rich Measures]

>Some commercial amps, like, MLA2500, apply ht and filament power
>together to g-g tubes. Is this contrary to manufacturer's
>recommendations and/or bad practice?
-  Cathode-flaking can result from allowing cathode current to flow 
before the oxide-cathode has reached operating temperature.  If 
oxide-cathode tubes are biased to cutoff so that no cathode current can 
flow during preheat, all potentials can be applied together.  The normal 
way of accomplishing this is to open the relay-control line during 
preheat, which prevents drive from being applied, and applies cutoff 
bias.  This is how the MLA-2500 does it.  
later, Steve

cheers
Rich...

R. L. Measures, 805-386-3734, AG6K   


--
FAQ on WWW:               http://www.contesting.com/ampfaq.html
Submissions:              amps@contesting.com
Administrative requests:  amps-REQUEST@contesting.com
Problems:                 owner-amps@contesting.com
Search:                   http://www.contesting.com/km9p/search.htm